Glossary
Centromere drive: a model that proposes selection for the unequal transmis-
sion of competing centromeres in female meiosis.
Kinetochore formation : the formation of a protein structure that assembles on
the centromere and links the chromosome to microtubule polymers, which are
attached to the mitotic spindle during mitosis and meiosis in eukaryotes. The
kinetochore contains two regions: an inner kinetochore, which is tightly
associated with the centromeric DNA; and an outer kinetochore, which
interacts with the microtubules.
Negative selection : natural selection that selectively removes rare alleles that
are deleterious.
Positive selection: natural selection that favors a single allele, resulting in allele
frequency continuously shifting in one direction.
Recombinational cold spots: the genomic regions where meiotic recombina-
tion is severely or completely suppressed in contrast to the genomic regions
where meiotic recombination occurs normally or more frequently.
Sister chromatid cohesion: the joining of the sister chromatids of a replicated
chromosome along the entire length of the chromosome, a process that occurs
during mitosis. This cohesion cycle is crucial for high-fidelity transmission of
chromosomes.
Box 1. Unanswered questions
Roles of centromeric sequences
Both CRs and centromeric satellite repeats interact with CENH3 in all
plant species that have been investigated. Do these two classes of
centromeric repeat have similar or distinct roles in centromere
function? Non-CRs and single-copy sequences can also interact with
CENH3 in some organisms [11,25,40] . Are these CENH3-binding
sequences all required for centromere formation? The development
of artificial plant chromosomes might provide new tools to study
centromere structure and function. What are the minimal require-ments for assembly of a highly efficient artificial chromosome?
Divergence of centromeric components
Centromere drive has been proposed to explain the rapid diver-gence of centromeric DNA and proteins (e.g. CENH3 and/or CENP-C)
in most plants and animals. This model might also account for the
disappearance of CentO and CRRs from functional centromeres of
Oryza brachyantha, a wild rice species that diverged from Oryza
sativa (rice) 7–9 Mya. However, conserved CR sequences, cen-tromeric satellite repeats and CENH3 were found in multiple grass
species: for example, rice and maize, which diverged from each
other 50–70 Mya. Why have centromeric repeats undergone such
marked changes inO. brachyanthabut not in rice and maize? Are
there genetic factors that could suppress the process of centromere
drive?
Evolutionary stage of rice Cen8
最后一段写不下在图片里
……童鞋……你用的什么翻译软件啊……念不通啊……
你不愿意回答就算了呗,实在不行我自己翻译不就是了
追答我只是见识过人家翻译文献赚钱而已,木有别的意思哈。。。不好意思嘞